A motion sensor indoor light switch is a device that uses motion detection to turn lights on and off. It is typically used in areas where lots of people are coming and going, such as in hallways, stairwells, and other public areas. The motion sensor works by detecting movement and then triggering the light switch to turn on and off accordingly. This allows for hands free operation and energy savings. It also keeps lights on when needed and off when not in use, saving energy and money. The definition of a motion sensor indoor light switch is that it is a device that uses motion detection to turn lights on and off. It is a great tool for those who want to save energy and money, as well as for those who want a hands-free way to turn lights on and off. Motion sensor indoor light switches are becoming more and more popular as people become more aware of the need to conserve energy and money.